Purified hydrogen is used in the manufacture of many products including metals, edible fats and oils, and semiconductors and microelectrodes. Purified hydrogen is also an important fuel source for many energy conversion devices. For example, many fuel cells use purified hydrogen and an oxidant to produce an electrical potential. A series of interconnected fuel cells is referred to as a fuel cell stack, and this stack may be referred to as a fuel cell system when combined with sources of oxidant and hydrogen gas. Various processes and devices may be used to produce the hydrogen gas that is consumed by the fuel cells.
One such device is a steam reformer, which reacts water and a carbon-containing feedstock in the presence of a steam reforming catalyst to produce a stream containing hydrogen gas. Examples of suitable carbon-containing feedstocks include alcohols and hydrocarbons. A particularly effective carbon-containing feedstock is methanol. Methanol steam reforming catalysts are typically low temperature shift (LTS) catalysts that have copper oxide as a primary active component. Although effective at reforming methanol and water into a reformate stream containing hydrogen gas, LTS catalysts are relatively quickly deactivated during use as a steam reforming catalyst and/or are pyrophoric. The catalysts may be deactivated by being reduced to an elemental metal, which may be sintered during further use of the catalyst. The pyrophoric nature of some LTS catalysts requires the catalysts to be shielded from contact with air when not being used so that the catalysts do not spontaneously combust.